1. Field of the Invention
The present invention generally relates to data inspection methods and apparatuses, and more particularly to a data inspection method and a data inspection apparatus for inspecting data which are written and read by an information processing apparatus.
2. Description of the Related Art
Conventionally, a storage medium such as a semiconductor memory and a storage device, and a peripheral device of an information processing apparatus are tested by writing test data to a write address of the storage medium. The test data written in the storage medium is read from the same address as the write address, and a data inspection is made by comparing the read test data and the test data.
The conventional test data has a value which is represented by a predetermined number of bits, such as 16 bits. The value of the test data continuously increases or decreases. That is, the test data is made up of a continuous data which continuously increases or decreases.
According to the continuous data which is conventionally used as the test data, it is possible to detect a fault when the test data written at a certain address and the test data read from this certain address differ. However, there was a problem in that it takes an extremely long time in order to detect a range of the fault and to determine the type of fault. This is because a complex logic system is required to determine if the fault is caused by a data dropout, data overlap or duplication, data mixing, data transformation or the like. The determination of the data mixing involves detection of a location where the data is mixed, and the determination of the data transformation involves detection of a location where a data xe2x80x9c1xe2x80x9d is transformed into a data xe2x80x9c0xe2x80x9d, for example.
In addition, when the information processing apparatus makes a write access to the external storage device, such as a hard disk drive, the following operations are involved. In terms of hardware, the write access starts from reading data from the semiconductor memory. The data read from the semiconductor memory are transferred to a channel input/output controller via an internal bus and a cache within a CPU, and the data are transferred from the channel input/output controller to the external storage device via an external bus and an input/output controller. The data transferred to the external storage device are written into a storage medium in logical blocks. When the operations described above are carried out by use of an operating system (OS), further processes of the OS are required, such as paging, and conversion between logical blocks and physical blocks. Therefore, even if the fault is detected by use of the continuous data, there was a problem in that it is extremely difficult to specify the exact location where the fault is generated.
Accordingly, it is a general object of the present invention to provide a novel and useful data inspection method and data inspection apparatus, in which the problems described above are eliminated.
Another and more specific object of the present invention is to provide a data inspection method and a data inspection apparatus which can specify a location of a fault when the fault is detected, and determine the kind of fault by a simple logic system.
Still another object of the present invention is to provide a data inspection method comprising the steps of (a) writing original test data in a memory region, (b) reading the test data from the memory region, and (c) comparing the read test data with the original test data, so as to make a data inspection, where the test data is formed by a plurality of cell data, each of the cell data includes a delimiter indicating a boundary between two adjacent cell data, a cell number indicating an order within the test data, a cell data length indicating a data length of the cell data, and pattern data, and each of the cell data in the test data has a cell data length which is variable. According to the data inspection method of the present invention, it is possible to specify the location of a fault generated in the cell data based on the cell data length of the cell data, because the cell data length of each cell data is variable.
A further object of the present invention is to provide the above data inspection method which further comprises the steps of (d) recognizing a cell data dropout, a cell data overlap or a cell data switching based on a size relationship of a cell number of the cell data in the read test data and an anticipated cell number, and whether or not the read test data includes a cell data having the anticipated cell number, if the cell number of the cell data in the read test data differs from a cell number of the cell data in the original test data. According to the data inspection method of the present invention, it is possible to recognize the kind of fault.
Another object of the present invention is to provide a data inspection apparatus which makes a data inspection by writing original test data in a memory region, reading the test data from the memory region, and comparing the read test data with the original test data, comprising test data generating means for generating the test data from a plurality of cell data, where each of the cell data includes a delimiter indicating a boundary between two adjacent cell data, a cell number indicating an order within the test data, a cell data length indicating a data length of the cell data, and pattern data, and each of the cell data in the test data has a cell data length which is variable. According to the data inspection apparatus of the present invention, it is possible to specify the location of a fault generated in the cell data based on the cell data length of the cell data, because the cell data length of each cell data is variable.
Still another object of the present invention is to provide the above data inspection apparatus which further comprises recognizing means for recognizing a cell data dropout, a cell data overlap or a cell data switching based on a size relationship of a cell number of the cell data in the read test data and an anticipated cell number, and whether or not the read test data includes a cell data having the anticipated cell number, if the cell number of the cell data in the read test data differs from a cell number of the cell data in the original test data. According to the data inspection apparatus of the present invention, it is possible to recognize the kind of fault.